From owner-freebsd-hardware Thu Jul 15 9:15:43 1999 Delivered-To: freebsd-hardware@freebsd.org Received: from feral.com (feral.com [192.67.166.1]) by hub.freebsd.org (Postfix) with ESMTP id 96ECE1559D; Thu, 15 Jul 1999 09:15:28 -0700 (PDT) (envelope-from mjacob@feral.com) Received: from semuta.feral.com (semuta [192.67.166.70]) by feral.com (8.8.7/8.8.7) with ESMTP id JAA13652; Thu, 15 Jul 1999 09:14:44 -0700 Date: Thu, 15 Jul 1999 09:14:44 -0700 (PDT) From: Matthew Jacob Reply-To: mjacob@feral.com To: Nick Hilliard Cc: radams@siscom.net, hardware@FreeBSD.ORG, stable@FreeBSD.ORG Subject: Re: Fibre Channel Controller In-Reply-To: <199907151052.LAA19073@beckett.earlsfort.iol.ie> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-hardware@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org > 3) Multi-Initiator on SCSI? Don't make me laugh. Every FC drive has two > ports as standard. Multi-Initiator is built in. A word of caution about this- there is a lot of buggy driver f/w for the dual ports. > 6) Fibrechannel drives do not consume 50% more than SCSI drives unless you What does this mean? > want to compare current SCSI drives with old FC ones. > > [...] > > 8) FC is bidirectional and is meant to be dual loop so really you have > 400Mbytes per second if you want to compare numbers. By the time Ultra160 > is stable 2Gb FC links will be available. Where has SCSI to go then? 80Mhz > I don't think so. 2Gb transceivers are readily available and 4Gb > transceivers are well on their way. No, wrong thinking here. This is theory. In practice unless you use switches you don't have full duplex. I don't know of any FC card that has the number of connectors to make it true dual-loop (2x{send,receive}), so that argument is bogus. A better point to note that the 2GB FC links are coming. > So what would I buy for my PC, well UltraSCSI of course, unless > gives me an FC cabinet. Then again if I was buying a couple of terabytes > then I would go FC, mirroring (RAID1) not RAID5 because drives are cheap > and write performance is better. This is my conclusion too, but the figure of merit isn't a "couple of terabytes", it's "numbers of addressable units". - To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hardware" in the body of the message